/*
 * Copyright 2017 Huawei Technologies Co., Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.servicecomb.swagger.invocation.arguments.consumer;

import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import io.servicecomb.swagger.invocation.SwaggerInvocation;
import io.servicecomb.swagger.invocation.arguments.ArgumentMapper;
import io.servicecomb.swagger.invocation.arguments.FieldInfo;

import java.util.Set;

/**
 * 透明RPC的典型场景
 * 因为没有标注指明RESTful映射方式
 * 所以，所有参数被包装为一个class，每个参数是一个field
 */
public class ConsumerArgumentToBodyField implements ArgumentMapper {
    private Class<?> swaggerParamType;

    // key为consumerArgs的下标
    private Map<Integer, FieldInfo> fieldMap;

    public ConsumerArgumentToBodyField(Class<?> swaggerParamType, Map<Integer, FieldInfo> fieldMap) {
        this.swaggerParamType = correctType(swaggerParamType);
        this.fieldMap = fieldMap;
    }

    protected Class<?> correctType(Class<?> swaggerParamType) {
        if (!Modifier.isAbstract(swaggerParamType.getModifiers())) {
            return swaggerParamType;
        }

        if (List.class.isAssignableFrom(swaggerParamType)) {
            return ArrayList.class;
        }

        if (Set.class.isAssignableFrom(swaggerParamType)) {
            return HashSet.class;
        }

        throw new Error("not support " + swaggerParamType.getName());
    }

    public Class<?> getSwaggerParamType() {
        return swaggerParamType;
    }

    @Override
    public void mapArgument(SwaggerInvocation invocation, Object[] consumerArguments) {
        try {
            Object body = swaggerParamType.newInstance();
            for (Entry<Integer, FieldInfo> entry : fieldMap.entrySet()) {
                FieldInfo info = entry.getValue();

                Object consumerParam = consumerArguments[entry.getKey()];
                Object swaggerParam = info.getConverter().convert(consumerParam);
                info.getField().set(body, swaggerParam);
            }
            invocation.setSwaggerArgument(0, body);
        } catch (Throwable e) {
            throw new Error(e);
        }
    }
}
